CN117665022A - Switchable monochromator system for neutron diffraction stress texture analysis - Google Patents

Abstract

The invention provides a switchable monochromator system for neutron diffraction stress texture analysis, which comprises an angle rotating table, an angle tilting table, a horizontal displacement table, a first monochromator and a second monochromator, wherein the angle tilting table is used for detecting the angle of the angle rotating table; the first monochromator and the second monochromator are used for generating different monochromatic neutron beams; the horizontal displacement table is used for adjusting the horizontal displacement of the first monochromator and the second monochromator; the angle tilting table is used for adjusting the tilting angle of the first monochromator or the second monochromator; the angle rotary table is used for adjusting the rotation angle of the first monochromator or the second monochromator. The invention solves the problems of monochromator switching and high-precision motion control in a smaller shielding space by adopting a structure integrating multi-axis motions such as angle rotation, angle inclination, horizontal displacement and the like and a high-precision encoder; by adopting a horizontal displacement table, the switching of high-resolution/high-neutron flux measurement modes and the setting of an empty beam state are realized through the switching of different types of monochromators.

Description

Switchable monochromator system for neutron diffraction stress texture analysis

Technical field

The present invention relates to neutron scattering technology, and in particular, to a switchable monochromator system for neutron diffraction stress texture analysis.

Background technique

Neutron diffraction technology is one of the methods to non-destructively analyze the stress and texture inside crystal materials. Different materials have different requirements for the resolution of the neutron diffraction spectrometer and the neutron flux at the sample. For example, metal materials such as nickel-based high-temperature alloys and zirconium alloys require high resolution spectrometers, while materials such as ceramics and geotechnical materials require high neutron flux at the sample.

There is an existing Chinese patent with publication number CN102253405B, which discloses a multi-axis neutron monochromator attitude adjustment device. The adjustment device includes a mechanical platform body and a control system connected to the mechanical platform body through cables. The mechanical platform body includes a rotating platform arranged on the chassis. The rotating platform is provided with a translation regulator. On the translation regulator There is a tilt adjuster above, and a monochromator indexing turntable is set on the tilt adjuster. Each motion mechanism of the mechanical table body drives the monochromator to perform position combination adjustment with multiple degrees of freedom; the control system includes a control software equipped with Industrial control computer and motor control unit that controls the stepper motor through the driver. This device can adjust the horizontal, vertical, tilt and rotation posture of a single neutron monochromator, but is not suitable for switching two or more monochromators in a small space.

Most neutron diffraction spectrometers based on reactor neutron sources are equipped with only one monochromator. Configuring two different types of monochromators on one neutron diffraction spectrometer can meet the testing needs of more materials and reduce the cost of the spectrometer. Development costs. The E3 spectrometer at the Neutron Scattering Center in Berlin, Germany uses a rotational transposition method to switch between three different monochromators. The STRESS-SPEC spectrometer at the Munich Neutron Scattering Center uses an up and down movement method to switch monochromators. However, this type of monochromator The device switching method requires a large space, and there are currently no public reports on the specific technical details of implementing related functions.

Therefore, the inventor believes that there is a need to provide a switchable monochromator system for neutron diffraction stress texture analysis, which can solve the problems of monochromator switching and high-precision motion control in a small shielding space.

Contents of the invention

In view of the deficiencies in the prior art, the purpose of the present invention is to provide a switchable monochromator system for neutron diffraction stress texture analysis.

According to a switchable monochromator system for neutron diffraction stress texture analysis provided by the present invention, it includes: an angle rotation stage, an angle tilt stage, a horizontal displacement stage, a first monochromator and a second monochromator, The angle rotation stage, the angle tilt stage and the horizontal displacement stage are arranged in sequence from bottom to top, and the first monochromator and the second monochromator are respectively installed on the horizontal displacement stage; The first monochromator and the second monochromator are used to generate different monochromatic neutron beams; the horizontal displacement stage is used to adjust the horizontal displacement of the first monochromator and the second monochromator. , making the first monochromator or the second monochromator face the white light neutron beam; the angle tilting table is used to adjust the tilt angle of the first monochromator or the second monochromator , focusing the monochromatic neutron beam at the center of the sample test area; the angle rotation stage is used to adjust the rotation angle of the first monochromator or the second monochromator, adjusting the first The takeoff angle of the monochromator or said second monochromator relative to the white light neutron beam.

Preferably, the first monochromator is a double-focused perfect single crystal silicon monochromator, and the diffraction crystal planes of the first monochromator include 311 and 400, which are used to generate a high-resolution monochromatic neutron beam; The second monochromator is a highly directional pyrolytic graphite monochromator. The diffraction crystal planes of the second monochromator include 002 and 004, which are used to generate high-flux monochromatic neutron beams.

Preferably, the incident surface of the first monochromator and the second monochromator is perpendicular to the horizontal plane, and the vertical center line of the incident surface of the first monochromator and the second monochromator is perpendicular to the horizontal plane. The central axis of the displacement stage; the horizontal center line of the incident surface of the first monochromator is parallel to the central axis of the horizontal displacement stage; the horizontal center line of the incident surface of the second monochromator intersects with the center line of the horizontal displacement stage axis.

Preferably, the angle rotation table includes an angle rotation table fixed seat and an angle rotation table, the angle rotation table is installed on the angle rotation table fixed seat, and the angle rotation table can be fixed relative to the angle rotation table. The base performs rotational movement; the rotation range of the angle rotation table is +/-180°, and the angle accuracy is ±0.002°; the angle rotation limit switch position is provided on the fixed seat of the angle rotation table, and the angle rotation limit Switch position is +/-60°.

Preferably, the rotation axis of the angle rotation table is parallel to the vertical center line of the incident surface of the first monochromator and the second monochromator, and the rotation axis of the angle rotation table passes through the geometry of the horizontal displacement stage. At the center, the rotation axis of the angle rotation table intersects perpendicularly with the central axis of the horizontal displacement stage.

Preferably, the angle tilt table includes an angle tilt table fixed base and an angle tilt table arc-shaped table. The angle tilt table arc-shaped table is installed on the angle tilt table fixed base, and the angle tilt table arc-shaped table can Swing motion along the arc-shaped track of the angle tilt table on the fixed seat of the angle tilt table; the rotation range of the angle tilt table is +/-10°, and the angle accuracy is ±0.005°; An angle tilt limit switch position is provided, and the angle tilt limit switch position is +/-5°.

Preferably, the angle tilt table fixed seat is installed on the angle rotation table, and the rotation axis of the angle rotation table passes through the geometric center of the arc-shaped table of the angle tilt table.

Preferably, the horizontal displacement stage includes a horizontal displacement stage fixed seat, a monochromator support slider, and a trapezoidal screw. The trapezoidal screw is drivingly connected to the monochromator support slider. The monochromator support slider is The block is installed on the fixed base of the horizontal displacement stage and can move horizontally; the displacement range of the horizontal displacement stage is +/-249.25mm, and the positioning accuracy is ±0.0015mm; the fixed base of the horizontal displacement stage is provided with a horizontal Displacement limit switch position, the horizontal displacement limit switch position is +/-240mm.

Preferably, the first monochromator and the second monochromator are respectively installed on the monochromator support slider through supports, and the horizontal displacement stage fixed seat is installed on the arc-shaped angle tilt stage. On the countertop.

Preferably, when no neutron diffraction experiment is performed, the gap between the first monochromator and the second monochromator faces the white light neutron beam.

Compared with the prior art, the present invention has the following beneficial effects:

The present invention solves the problem of monochromator switching and high-precision motion control in a small shielded space by using a multi-axis motion integrated structure such as angular rotation, angular tilt and horizontal displacement, and a high-precision encoder; by using horizontal displacement stage, that is, a structure in which the monochromator support slider can be translated along the horizontal displacement stage fixed seat 101 driven by a stepper motor, which solves the problem of switching between a dual-focus perfect single crystal silicon monochromator and a highly directional pyrolytic graphite monochromator. ; By switching different types of monochromators, the switching of high-resolution/high-medium neutron flux measurement modes and the setting of the empty beam state are achieved; the high-precision encoder can ensure perfect double focusing of single-crystal silicon monochromators and high directional heat The coincidence degree between the vertical axis of the graphite monochromator and the rotation axis of the angle rotation table is within the error range, ensuring the accuracy of the Bragg angle of the monochromator.

Description of drawings

Other features, objects and advantages of the present invention will become more apparent by reading the detailed description of the non-limiting embodiments with reference to the following drawings:

Figure 1 is a schematic structural diagram of a switchable monochromator system mainly used for neutron diffraction stress texture analysis according to the present invention;

Figure 2 is a schematic structural diagram of the angle rotation table mainly embodying the present invention;

Figure 3 is a schematic structural diagram of an angle tilting table mainly embodying the present invention;

Figure 4 is a schematic structural diagram of the horizontal displacement stage mainly embodied in the present invention;

Figure 5 is a schematic diagram of the present invention mainly embodying the neutron diffraction experiment;

Fig. 6 is a schematic diagram mainly showing the empty beam state of the present invention.

Shown in the picture:

Angle rotary table 100 Angle rotary table fixed base 101

Angle rotating table 102 Angle tilting table 200

Angle tilt table fixed base 201 Angle tilt table arc track 202

Angle tilt stage curved table 203 Horizontal displacement stage 300

Horizontal displacement stage fixed base 301 Monochromator support slider 302

Trapezoidal screw 303 First monochromator 400

Second monochromator 500

Detailed ways

The present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

As shown in Figure 1, a switchable monochromator system for neutron diffraction stress texture analysis provided according to the present invention includes: an angle rotation stage 100, an angle tilt stage 200, a horizontal displacement stage 300, a first monochromator The color detector 400 and the second monochromator 500, the angle rotation stage 100, the angle tilt stage 200 and the horizontal displacement stage 300 are arranged in sequence from bottom to top. The first monochromator 400 and the second monochromator 500 are respectively installed on the horizontal displacement stage. On the stage 300; the first monochromator 400 and the second monochromator 500 are used to generate different monochromatic neutron beams; the horizontal displacement stage 300 is used to adjust the level of the first monochromator 400 and the second monochromator 500. The displacement is adjusted so that the first monochromator 400 or the second monochromator 500 faces the white light neutron beam; the angle tilting stage 200 is used to adjust the tilt angle of the first monochromator 400 or the second monochromator 500 so that the monochromator 400 or the second monochromator 500 faces the white light neutron beam. The color neutron beam is focused on the center of the sample test area; the angle rotation stage 100 is used to adjust the rotation angle of the first monochromator 400 or the second monochromator 500, and then adjust the take-off angle relative to the white light neutron beam to generate Monochromatic neutron beams of different wavelengths.

Monochromators are used to generate monochromatic neutron beams in neutron diffraction stress texture analysis. Different samples or engineering components have different requirements for spectrometer resolution or neutron flux at the sample. The monochromatic neutron beam has a key impact on the resolution of the spectrometer or the neutron flux at the sample. The key point of its design is to achieve high-resolution or high-medium neutron flux measurement modes and switching within a limited shielding space, while maintaining high accuracy in angular rotation, angular tilt, and translation.

Since the angle tilt stage 200 is provided on the angle rotation stage 100 and the horizontal displacement stage 300 is provided on the angle tilt stage 200, the angle rotation stage 100 simultaneously adjusts the rotation angles of the angle tilt stage 200 and the horizontal displacement stage 300, and its main purpose is to adjust the horizontal displacement. The rotation angle of the stage 100 is then adjusted to the rotation angle of the first monochromator 400 or the second monochromator 500, that is, the take-off angle relative to the white light neutron beam is adjusted to generate monochromatic neutron beams of different wavelengths.

The first monochromator 400 is a double-focused perfect single crystal silicon monochromator, which uses diffraction crystal planes (311) and (400) to generate high-resolution monochromatic neutron beams to achieve high-resolution measurement mode. . The second monochromator 500 is a highly directional pyrolytic graphite monochromator. The diffraction crystal planes used are (002) and (004). It is used to generate a high-flux monochromatic neutron beam to achieve high-medium neutron flux measurement mode. .

The incident surface of the first monochromator 400 and the second monochromator 500 is perpendicular to the horizontal plane, and the vertical center line of the incident surface of the first monochromator 400 and the second monochromator 500 is perpendicular to the central axis of the horizontal displacement stage 300; first The horizontal center line of the incident surface of the monochromator 400 is parallel to the central axis of the horizontal displacement stage 300 ; the horizontal center line of the incident surface of the second monochromator 500 intersects with the central axis of the horizontal displacement stage 300 .

As shown in Figure 2, the angle rotation table 100 is installed on the base. The angle rotation table 100 includes an angle rotation table fixed base 101 and an angle rotation table 102. The angle rotation table 102 is installed on the angle rotation table fixed base 101, and the angle rotation table 102 is installed on the angle rotation table fixed base 101. The table 102 can rotate relative to the angle rotation table fixed base 101 . The angle rotation table 102 of the angle rotation table 100 is connected to a stepper motor capable of driving the rotation table through a rotating mechanism. An encoder is installed on one end of the stepper motor transmission shaft as an angle reader of the angle rotation table 102 . The rotation range of the angle rotation table 100 is +/-180°, and the angle accuracy is ±0.002°; the angle rotation limit switch position is set on the fixed base 101 of the angle rotation table, and the angle rotation limit switch position is +/-60°. It can be adjusted according to actual usage.

The rotation axis of the angle rotation table 102 is parallel to the vertical center line of the incident surface of the first monochromator 400 and the second monochromator 500. The rotation axis of the angle rotation table 102 passes through the geometric center of the horizontal displacement stage 300. The rotation of the angle rotation table 102 The axis intersects perpendicularly with the central axis of the horizontal displacement stage 300 .

As shown in Figure 3, the angle tilt stage 200 is used to adjust the tilt angle of the monochromator 400 or the monochromator 500 so that the monochromatic neutron beam can be more accurately focused on the center of the sample test area. The angle tilt table 200 includes an angle tilt table fixed base 201 and an angle tilt table arc table 203. The angle tilt table arc table 203 is installed on the angle tilt table fixed base 201. The angle tilt table arc table 203 can be fixed along the angle tilt table. The angle-inclined platform arc track 202 on the base 201 performs a swinging motion. The arc-shaped table 203 of the angle tilt table 200 is connected to a stepper motor that can drive the arc-shaped table to rotate through a rotating mechanism. An encoder is installed on one end of the stepper motor transmission shaft as the position reader angle of the arc-shaped table 203. The rotation range of the tilt table 200 is +/-10°, and the angle accuracy is ±0.005°; the angle tilt limit switch position is provided on the angle tilt table fixed base 201, and the angle tilt limit switch position is +/-5°. It can be adjusted according to actual usage.

The angle tilt table fixed base 201 is installed on the angle rotation table 102, and the rotation axis of the angle rotation table 102 passes through the geometric center of the angle tilt table arc table 203.

As shown in Figure 4, the horizontal displacement stage 300 is used to adjust the horizontal displacement of the monochromator 400 and the monochromator 500, so that the double-focused perfect single crystal silicon monochromator 400 or the highly directional pyrolytic graphite monochromator 500 faces white light. Neutron beam, generates a monochromatic neutron beam with high resolution or high neutron flux, and realizes high resolution or high neutron flux measurement mode and its switching. The horizontal displacement stage 300 includes a horizontal displacement stage fixed seat 301, a monochromator support slider 302, and a trapezoidal screw 303. The trapezoidal screw 303 is transmission connected with the monochromator support slider 302. The monochromator support slider 302 is installed horizontally. The displacement stage is fixed on the base 301 and can move horizontally. The monochromator support slider 302 is connected through a screw rod to a stepper motor that can drive the screw rod to rotate and drive the support slider 302 to translate. An encoder is installed at one end of the screw rod as a position reader for the support slider 302. The displacement range of the horizontal displacement stage 300 is +/-249.25mm, and the positioning accuracy is ±0.0015mm; the horizontal displacement limit switch position is provided on the fixed base 301 of the horizontal displacement stage, and the horizontal displacement limit switch position is +/-240mm. It can be adjusted according to actual usage.

The first monochromator 400 and the second monochromator 500 are respectively installed on the monochromator support slider 302 through supports, and the horizontal displacement stage fixed seat 301 is installed on the arc-shaped table 203 of the angle tilt stage.

When the neutron diffraction experiment is not performed, the gap between the first monochromator 400 and the second monochromator 500 faces the white light neutron beam and does not affect the transmission of the white light neutron beam.

As shown in Figures 5 and 6, the above-mentioned switchable monochromator system can be used to realize monochromator switching, thereby achieving switching of high-resolution/high-medium neutron flux measurement modes. Switching a dual-focus perfect monocrystalline silicon monochromator to a highly directional pyrolytic graphite monochromator or vice versa involves the following steps:

Step 1. Run the angle rotation stage 100 and adjust the rotation angle of the angle rotation stage 102 so that the horizontal displacement stage 300 is perpendicular to the white light neutron beam; in this embodiment, the horizontal displacement stage 300 is at the corresponding angle when it is perpendicular to the white light neutron beam. The rotation angle of the rotating table 102 is 0°; this step is mainly because direct switching will cause the monochromator to collide with other machinery and damage the monochromator;

Step 2, run the horizontal displacement stage 300, adjust the displacement of the monochromator support slider 302 on the horizontal displacement stage 300, so that the geometric center of the double-focused perfect single crystal silicon monochromator or the highly directional pyrolytic graphite monochromator is aligned with the white light. The geometric center of the neutron beam coincides; if no neutron diffraction experiment is performed, make the center of the gap between the first monochromator 400 and the second monochromator 500 coincide with the geometric center of the white light neutron beam; this step is to switch the monochromator or empty beam state;

Step 3: Run the angle rotation stage 100 and adjust the rotation angle of the angle rotation stage 102 to the set value; it should be noted that the crystal plane orientation of the first monochromator 400 is (400). When using the diffraction crystal plane (400), The Bragg angle is the rotation angle reading value of the angle rotation table 102; when using the diffraction crystal plane (311), the Bragg angle is the rotation angle of the angle rotation table 102 plus 25.245°; the crystal plane orientation of the second monochromator 500 is (002) , the angle between the incident surface and the central axis of the horizontal displacement stage is 30°. When using the diffraction crystal plane (002) or (004), the Bragg angle is the rotation angle reading value plus 30°; according to Bragg's law 2dsinθ=λ, the monochromatic color can be calculated The wavelength of the neutron beam;

Step 4, run the angle tilt stage 200, adjust the tilt angle of the arc-shaped table 203 of the angle tilt stage, so that the monochromatic neutron beam is focused on the center of the test area of the sample or workpiece; this step is to reduce the actual measurement area and theoretical measurement regional error, improve test accuracy, and at the same time increase the neutron flux in the test area.

In this application, the first monochromator 400 and the second monochromator 500 are arranged on the monochromator support slider 302 of the horizontal displacement stage 300. By translating the monochromator support slider 302, dual-focus perfect single crystals can be achieved. Silicon monochromator 400 or highly directional pyrolytic graphite monochromator 500 monochromatic white light neutron beam, thereby achieving switching between high resolution or high neutron flux measurement modes.

This application adopts a horizontal displacement stage 300, that is, a structure in which the monochromator support slider 302 can be translated along the horizontal displacement stage fixed seat 301 under the drive of a stepper motor, to solve the problem of dual-focus perfect single crystal silicon monochromator and highly directional thermal Solve the problem of graphite monochromator switching; by switching different types of monochromators, the switching of high-resolution/high-medium neutron flux measurement modes and the setting of the empty beam state are achieved.

This application solves the problem of monochromator switching and high-precision motion control in a small shielded space by using a multi-axis motion integrated structure such as angular rotation, angular tilt, and horizontal displacement, as well as a high-precision encoder; through high-precision encoding The device can ensure that the coincidence degree between the vertical axis of the double-focused perfect single crystal silicon monochromator and the highly directional pyrolytic graphite monochromator and the rotation axis of the angle rotating table 102 is within the error range, ensuring the accuracy of the Bragg angle of the monochromator.

In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", The orientations or positional relationships indicated by "bottom", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings. They are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying the device referred to. Or elements must have a specific orientation, be constructed and operate in a specific orientation and therefore are not to be construed as limitations on the application.

Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above. Those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. The embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily without conflict.

Claims (10)

1. A switchable monochromator system for neutron diffraction stress texture analysis, characterized by including: an angle rotation stage (100), an angle tilt stage (200), a horizontal displacement stage (300), a first The monochromator (400) and the second monochromator (500), the angle rotation stage (100), the angle tilt stage (200) and the horizontal displacement stage (300) are arranged in sequence from bottom to top, so The first monochromator (400) and the second monochromator (500) are respectively installed on the horizontal displacement stage (300); The first monochromator (400) and the second monochromator (500) are used to generate different monochromatic neutron beams; The horizontal displacement stage (300) is used to adjust the horizontal displacement of the first monochromator (400) and the second monochromator (500), so that the first monochromator (400) or the The second monochromator (500) faces the white light neutron beam; The angle tilt stage (200) is used to adjust the tilt angle of the first monochromator (400) or the second monochromator (500) so that the monochromatic neutron beam is focused on the sample test area. Central location; The angle rotation stage (100) is used to adjust the rotation angle of the first monochromator (400) or the second monochromator (500). The takeoff angle of the second monochromator (500) relative to the white light neutron beam. 2. The switchable monochromator system for neutron diffraction stress texture analysis as claimed in claim 1, characterized in that the first monochromator (400) is a dual-focus perfect single crystal silicon monochromator. , the diffraction crystal planes of the first monochromator (400) include 311 and 400, used to generate a high-resolution monochromatic neutron beam; The second monochromator (500) is a highly directional pyrolytic graphite monochromator. The diffraction crystal planes of the second monochromator (500) include 002 and 004, which are used to generate high-flux monochromatic neutrons. bundle. 3. The switchable monochromator system for neutron diffraction stress texture analysis as claimed in claim 1, characterized in that the first monochromator (400) and the second monochromator (500 ) is perpendicular to the horizontal plane, and the vertical center line of the incident surface of the first monochromator (400) and the second monochromator (500) is perpendicular to the central axis of the horizontal displacement stage (300); The horizontal centerline of the incident surface of the first monochromator (400) is parallel to the central axis of the horizontal displacement stage (300); The horizontal centerline of the incident surface of the second monochromator (500) intersects with the central axis of the horizontal displacement stage (300). 4. The switchable monochromator system for neutron diffraction stress texture analysis as claimed in claim 1, characterized in that the angle rotation stage (100) includes an angle rotation stage fixed seat (101) and an angle rotation stage. Table (102), the angle rotating table (102) is installed on the angle rotating table fixed seat (101), and the angle rotating table (102) can move relative to the angle rotating table fixed seat (101) rotational motion; The rotation range of the angle rotary table (100) is +/-180°, and the angle accuracy is ±0.002°; The angle rotation limit switch position is provided on the angle rotation table fixed seat (101), and the angle rotation limit switch position is +/-60°. 5. The switchable monochromator system for neutron diffraction stress texture analysis as claimed in claim 4, characterized in that the rotation axis of the angle rotation table (102) is parallel to the first monochromator (400) and the vertical center line of the incident surface of the second monochromator (500), the rotation axis of the angle rotation table (102) passes through the geometric center of the horizontal displacement table (300), the angle rotation table ( The rotation axis of 102) intersects perpendicularly with the central axis of the horizontal displacement stage (300). 6. The switchable monochromator system for neutron diffraction stress texture analysis as claimed in claim 4, wherein the angle tilt stage (200) includes an angle tilt stage fixed seat (201) and an angle tilt stage. The curved table top (203) of the angle tilt table is installed on the fixed seat (201) of the angle tilt table. The curved table top (203) of the angle tilt table can tilt along the angle. The angle-inclined table arc track (202) on the table fixed base (201) performs swing motion; The rotation range of the angle tilt table (200) is +/-10°, and the angle accuracy is ±0.005°; An angle tilt limit switch position is provided on the angle tilt table fixed seat (201), and the angle tilt limit switch position is +/-5°. 7. The switchable monochromator system for neutron diffraction stress texture analysis as claimed in claim 6, characterized in that the angle tilt table fixed seat (201) is installed on the angle rotation table (102) The rotation axis of the angle rotating table (102) passes through the geometric center of the arc-shaped table (203) of the angle tilting table. 8. The switchable monochromator system for neutron diffraction stress texture analysis as claimed in claim 6, characterized in that the horizontal displacement stage (300) includes a horizontal displacement stage fixed seat (301), a monochromator The monochromator support slider (302) and the trapezoidal screw (303) are drivingly connected to the monochromator support slider (302). The monochromator support slider (302) is installed. On the horizontal displacement stage fixed seat (301), and capable of horizontal movement; The displacement range of the horizontal displacement stage (300) is +/-249.25mm, and the positioning accuracy is ±0.0015mm; A horizontal displacement limit switch position is provided on the horizontal displacement stage fixed seat (301), and the horizontal displacement limit switch position is +/-240mm. 9. The switchable monochromator system for neutron diffraction stress texture analysis as claimed in claim 8, characterized in that the first monochromator (400) and the second monochromator (500 ) are respectively installed on the monochromator support slider (302) through supports, and the horizontal displacement stage fixed seat (301) is installed on the arc-shaped table (203) of the angle tilt stage. 10. The switchable monochromator system for neutron diffraction stress texture analysis as claimed in claim 1, characterized in that when the neutron diffraction experiment is not performed, the first monochromator (400) and The gap between the second monochromators (500) faces the white light neutron beam.